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Title: Phase Imprinting in Equilibrating Fermi Gases: The Transience of Vortex Rings and Other Defects

Abstract

We present numerical simulations of phase imprinting experiments in ultracold trapped Fermi gases, which were obtained independently and are in good agreement with recent experimental results. Our focus is on the sequence and evolution of defects using the fermionic time-dependent Ginzburg-Landau equation, which contains dissipation necessary for equilibration. In contrast to other simulations, we introduce small, experimentally unavoidable symmetry breaking, particularly that associated with thermal fluctuations and with the phase-imprinting tilt angle, and we illustrate their dramatic effects. As appears consistent with experiment, the former causes vortex rings in confined geometries to move to the trap surface and rapidly decay into more stable vortex lines. The latter aligns the precessing and relatively long-lived vortex filaments, rendering them difficult to distinguish from solitons.

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Advanced Scientific Computing Research (ASCR) (SC-21); USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1357032
DOE Contract Number:
AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 113; Journal Issue: 12
Country of Publication:
United States
Language:
English

Citation Formats

Scherpelz, Peter, Padavić, Karmela, Rançon, Adam, Glatz, Andreas, Aranson, Igor S., and Levin, K. Phase Imprinting in Equilibrating Fermi Gases: The Transience of Vortex Rings and Other Defects. United States: N. p., 2014. Web. doi:10.1103/PhysRevLett.113.125301.
Scherpelz, Peter, Padavić, Karmela, Rançon, Adam, Glatz, Andreas, Aranson, Igor S., & Levin, K. Phase Imprinting in Equilibrating Fermi Gases: The Transience of Vortex Rings and Other Defects. United States. doi:10.1103/PhysRevLett.113.125301.
Scherpelz, Peter, Padavić, Karmela, Rançon, Adam, Glatz, Andreas, Aranson, Igor S., and Levin, K. Mon . "Phase Imprinting in Equilibrating Fermi Gases: The Transience of Vortex Rings and Other Defects". United States. doi:10.1103/PhysRevLett.113.125301.
@article{osti_1357032,
title = {Phase Imprinting in Equilibrating Fermi Gases: The Transience of Vortex Rings and Other Defects},
author = {Scherpelz, Peter and Padavić, Karmela and Rançon, Adam and Glatz, Andreas and Aranson, Igor S. and Levin, K.},
abstractNote = {We present numerical simulations of phase imprinting experiments in ultracold trapped Fermi gases, which were obtained independently and are in good agreement with recent experimental results. Our focus is on the sequence and evolution of defects using the fermionic time-dependent Ginzburg-Landau equation, which contains dissipation necessary for equilibration. In contrast to other simulations, we introduce small, experimentally unavoidable symmetry breaking, particularly that associated with thermal fluctuations and with the phase-imprinting tilt angle, and we illustrate their dramatic effects. As appears consistent with experiment, the former causes vortex rings in confined geometries to move to the trap surface and rapidly decay into more stable vortex lines. The latter aligns the precessing and relatively long-lived vortex filaments, rendering them difficult to distinguish from solitons.},
doi = {10.1103/PhysRevLett.113.125301},
journal = {Physical Review Letters},
number = 12,
volume = 113,
place = {United States},
year = {Mon Sep 01 00:00:00 EDT 2014},
month = {Mon Sep 01 00:00:00 EDT 2014}
}
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